Last month, Julian sold 7 books for every 6 that Doug sold. Overall, Julian sold 8 more books than Doug. What was the total number of books sold last month?
J = 7/6 D
J = D+ 8
so
7/6 D = D + 8
7 D = 6 D +48
D= 48
then J = D + 8 = 56
total = 48 + 56 = 104